Influence of Geometrical Parameters, Wall Angle and Part Shape on Thickness Reduction of Single Point Incremental Forming

摘要

The aim of this paper is to study the thickness reduction during the whole single point incremental forming process. The experimental setup is realized in such a way that the blank sheet is in the vertical position and forming is done using an anthropomorphic robot with six degrees of freedom. The vertical positioning of the blank sheet allows the on-line visualization using an optical measuring system of the major and minor strains and of the thickness reduction. The wall angle varied between values of 450, 550 and 650 respectively. The logarithmic major strain and minor strains and logarithmic thickness reduction were analyzed in order to allow a comparison with values obtained based on the sine law. The results show that indeed, the maximal values of the thickness reduction observe the sine law for the parts but only after a “critical value” of the part's height is reached, the variation of the thickness reduction on the lateral faces of the pyramidal frustum are large, the thickness reduction is significant in some areas as compared to the maximal values.